The Tagetes genus is a member of the family Asteraceae, alternatively known as Compositae, and comprises around thirty species of strongly scented annual or perennial herbs. Tagetes are native from Arizona and New Mexico to Argentina. Cultivated genera include Tagetes erecta, commonly referred to as African marigold, Tagetes patula, French marigold, Tagetes erecta×patula, also known as triploid marigolds, and Tagetes tenuifolia, also known as Tagetes signata or commonly signet marigold.
Cultivated marigolds perform well in dry or moist conditions with strongly scented, showy flowers that are excellent in borders and as cut flowers. They produce a long-term display of colors, which include yellow, orange, and gold, with shades of red and maroon from the triploid and French types. Flowers range in size from 2.5 cm for the French varieties to as broad a 13 cm for some of the African varieties. Plants range from 15 to 91 cm in height and fill in well in the garden. Of the cultivated marigolds, the French marigolds are especially valued in the landscape as a colorful upright-mounding border plant. Under high humidity and high night temperatures, French marigolds typically stretch and exhibit reduced flowering.